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84-531: In 1883, the eruption of Krakatoa led to visual tracking of subsequent volcanic ash in the stratosphere. This visual tracking led to the discovery of easterly winds between 25 and 30 km above the surface. The winds were then called the Krakatau easterlies. In 1908, data balloons launched above Lake Victoria in Africa recorded westerly winds in the stratospheric levels of the atmosphere . These findings, at

168-420: A bulge indicative of magma near the surface at the site that became Anak Krakatau . The fate of northern Krakatoa has been the subject of some dispute among geologists. It was initially proposed that the island had been blown apart by the force of the eruption. Most of the material deposited by the volcano is magmatic in origin, and the caldera formed by the eruption is not extensively filled with deposits from

252-420: A continued eruption. The eruption caused a volcanic winter . In the year following the eruption, average Northern Hemisphere summer temperatures fell by 0.4 °C (0.72 °F). The record rainfall that hit Southern California during the water year from July 1883 to June 1884 – Los Angeles received 970 millimetres (38.18 in) and San Diego 660 millimetres (25.97 in) – has been attributed to

336-402: A distance. No signs of further activity were seen until 1913 when an eruption was reported. An investigation could find no evidence the volcano was awakening. It was determined that what had been mistaken for renewed activity had been a major landslide (possibly the one which formed the second arc to Rakata's cliff). Examinations after 1930 of bathymetric charts made in 1919 show evidence of

420-506: A few moments, but . . . one after another, they were washed down and carried far away by the rushing waters. You can see the marks on the hill side where the fight for life took place. Some . . . dragged others down with them. They would not let go their hold, nor could those above them release themselves from this death-grip." Away from the coasts of the Sunda Strait, the waves reached a height of 4 metres on Southern Sumatra. One person

504-457: A fragment of Danan, was left; Poolsche Hoed had disappeared. The huge amount of material the volcano deposited drastically altered the ocean floor. The huge amount of ignimbrite deposits largely filled the 30–40 m (98–131 ft) deep basin around the mountain. The land masses of Verlaten and Lang islands were increased, as was the western part of the remnant of Rakata. Much of this gained material quickly eroded, but volcanic ash remains

588-468: A major contributor and the QBO is now simulated in a growing number of climate models. Effects of the QBO include mixing of stratospheric ozone by the secondary circulation caused by the QBO, modification of monsoon precipitation, and an influence on stratospheric circulation in northern hemisphere winter (mediated partly by a change in the frequency of sudden stratospheric warmings ). Easterly phases of

672-434: A minimum of 4,000 km (1,500 sq mi). Pyroclastic deposits thought to be from the flows have been found on Southeast Sumatra, and northwest of the volcano on the islands of Sebesi, Sebuku and Lagoendi, while on Southwest Sumatra the flows burnt victims. They travelled 40 km (25 mi) across the Sunda Strait. Once they hit Southern Sumatra, they incinerated entire villages and burned all vegetation. 2,000 of

756-679: A more secular approach into historical study. According to John Tosh , "From the High Middle Ages (c.1000–1300) onwards, the written word survives in greater abundance than any other source for Western history." Western historians developed methods comparable to modern historiographic research in the 17th and 18th centuries, especially in France and Germany, where they began investigating these source materials to write histories of their past. Many of these histories had strong ideological and political ties to their historical narratives. In

840-660: A rain of hot ash fell around Ketimbang (now Katibung in Lampung Province) in Sumatra, known as 'The Burning Ashes of Ketimbang', killing approximately 1,000 people in Sumatra. The combination of pyroclastic flows , volcanic ash, and tsunamis associated with the Krakatoa eruptions had disastrous regional consequences. Some land in Banten , approximately 80 km south, was never repopulated; it reverted to jungle and

924-466: A significant part of the geological composition of these islands. The basin was 100 m (330 ft) deep before the eruption, and 200–300 m (660–980 ft) after. Two nearby sandbanks (called Steers and Calmeyer after the two naval officers who investigated them) were built up into islands by ashfall, but the sea later washed them away. Seawater on hot volcanic deposits on Steers and Calmeyer had caused steam to rise, which some mistook for

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1008-467: A small tsunami hit the shores of Java and Sumatra , 40 km (25 mi) away. On 27 August, four enormous explosions occurred, which marked the climax of the eruption. At 5:30 am, the first explosion was at Perboewatan, triggering a tsunami heading to Telok Betong , now known as Bandar Lampung. At 6:44   am, Krakatoa exploded again at Danan, with the resulting tsunami propagating eastward and westward. The third and largest explosion, at 10:02 am,

1092-709: Is disagreement concerning exactly when prehistory becomes history, and when proto-writing became "true writing". However, invention of the first writing systems is roughly contemporary with the beginning of the Bronze Age in the late Neolithic of the late 4th millennium BCE . The Sumerian archaic cuneiform script and the Egyptian hieroglyphs are generally considered the earliest writing systems, both emerging out of their ancestral proto-literate symbol systems from 3400 to 3200 BCE, with earliest coherent texts from about 2600 BCE . The earliest chronologies date back to

1176-415: Is initially higher than 100 metres driven by the shocked water, basalt, and air. Bibliography Recorded history Recorded history or written history describes the historical events that have been recorded in a written form or other documented communication which are subsequently evaluated by historians using the historical method . For broader world history , recorded history begins with

1260-540: Is now the Ujung Kulon National Park . Ash fell 2,500 km away. Huge fields of floating pumice were reported for months after the event. There are numerous reports of groups of human skeletons floating across the Indian Ocean on rafts of volcanic pumice and washing up on the east coast of Africa up to a year after the eruption. An observation made two weeks after the eruption describes

1344-518: Is one of the earliest mentions of "pigtail of Brahmin boys". These poems also allude to historical incidents, ancient Tamil kings, the effect of war on loved ones and households. The Pattinappalai poem in the Ten Idylls group, for example, paints a description of the Chola capital, the king Karikala , the life in a harbor city with ships and merchandise for seafaring trade, the dance troupes,

1428-502: Is one of the few documents containing material relating to the Nāga and Yakkha peoples , indigenous inhabitants of Lanka prior to the legendary arrival of Prince Vijaya from Singha Pura of Kalinga. The Sangam literature offers a window into some aspects of the ancient South Indian culture, secular and religious beliefs, and the people. For example, in the Sangam era Ainkurunuru poem 202

1512-480: Is the knife?' . . . I will cut all our wrists and then we shall be released from our suffering sooner.' The knife could not be found. I felt a heavy pressure, throwing me to the ground. Then it seemed as if all the air was being sucked away and I could not breathe. . . . I felt people rolling over me . . . No sound came from my husband or children . . . I remember thinking, I want to . . . go outside . . . . but I could not straighten my back . . . I tottered, doubled up, to

1596-615: The Culavamsa "Lesser Chronicle", compiled by Sinhala monks, covers the period from the 4th century to the British takeover of Sri Lanka in 1815. The Culavamsa was compiled by a number of authors of different time periods. The combined work, sometimes referred to collectively as the Mahavamsa , provides a continuous historical record of over two millennia, and is considered one of the world's longest unbroken historical accounts. It

1680-575: The "father of history" composing his The Histories from the 450s to the 420s BCE. However, his contemporary Thucydides (c. 460 BCE – c. 400 BCE) is credited with having first approached history with a well-developed historical method in his work the History of the Peloponnesian War . Thucydides, unlike Herodotus, regarded history as being the product of the choices and actions of human beings, and looked at cause and effect, rather than as

1764-462: The 1883 eruption. This indicates that the island subsided into an empty magma chamber at the end of the eruption sequence rather than having been destroyed during the eruptions. Based on the findings of contemporary investigators, the established hypotheses assume that part of the island subsided before the first explosions on the morning of 27 August. This forced the volcano's vents to be below sea level, causing: Geological evidence does not support

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1848-407: The 1970s it was recognized by Richard Lindzen and James Holton that the periodic wind reversal was driven by atmospheric waves emanating from the tropical troposphere that travel upwards and are dissipated in the stratosphere by radiative cooling . The precise nature of the waves responsible for this effect was heavily debated; in recent years, however, gravity waves have come to be seen as

1932-501: The 2000s this was done using analogue recording methods such as cassettes and reel-to-reel tapes . With the onset of new technologies, there are now digital recordings , which may be recorded to compact disks. Nevertheless, historical record and interpretation often relies heavily on written records, partially because it dominates the extant historical materials, and partially because historians are used to communicating and researching in that medium. The historical method comprises

2016-403: The 20th century, academic historians began focusing less on epic nationalistic narratives, which often tended to glorify the nation or great men , to attempt more objective and complex analyses of social and intellectual forces. A major trend of historical methodology in the 20th century was a tendency to treat history more as a social science rather than as an art , which traditionally had been

2100-487: The Atlantic. Research has also been conducted investigating a possible relationship between ENSO ( El Niño–Southern Oscillation ) and the QBO. The Free University of Berlin supplies a QBO data set that comprises radiosonde observations from Canton Island , Gan , and Singapore . The plot below shows the QBO during the 1980s. The first significant observed deviation from the normal QBO since its discovery in early 1950s

2184-654: The Krakatoa eruption. There was no El Niño during that period as is usual when heavy rain occurs in Southern California, but many scientists doubt that there was a causal relationship. The eruption injected a tremendous amount of sulphur dioxide (SO 2 ) gas high into the stratosphere , which was subsequently transported by high-level winds all over the planet. This led to a global increase in sulphuric acid (H 2 SO 4 ) concentration in high-level cirrus clouds . The resulting increase in cloud reflectivity (or albedo ) reflected more incoming light from

2268-534: The QBO often coincide with more sudden stratospheric warmings, a weaker Atlantic jet stream, and cold winters in Northern Europe and the Eastern U.S. In contrast, westerly phases of the QBO often coincide with mild winters in the Eastern U.S. and a strong Atlantic jet stream with mild, wet winters in Northern Europe. In addition, the QBO has been shown to affect hurricane frequency during hurricane seasons in

2352-412: The accounts of the ancient world around the 4th millennium BCE, and it coincides with the invention of writing . For some geographic regions or cultures , written history is limited to a relatively recent period in human history because of the limited use of written records. Moreover, human cultures do not always record all of the information which is considered relevant by later historians, such as

2436-516: The advancement of technology. History can now be recorded through photography , audio recordings , and video recordings . More recently, Internet archives have been saving copies of webpages, documenting the history of the Internet . Other methods of collecting historical information have also accompanied the change in technologies; for example, since at least the 20th century, attempts have been made to preserve oral history by recording it. Until

2520-469: The apparent conflagration". This eruption also produced a Bishop's Ring around the sun by day, and a volcanic purple light at twilight. In 2004, an astronomer proposed the idea that the red sky shown in Edvard Munch 's 1893 painting The Scream is an accurate depiction of the sky over Norway after the eruption. Weather watchers of the time tracked and mapped the effects on the sky. They labelled

2604-402: The assumption that only subsidence before the explosion was the cause. For instance, the pumice and ignimbrite deposits are not of a kind consistent with a magma-seawater interaction. These findings have led to other hypotheses: A numerical model for a Krakatoa hydrovolcanic explosion and the resulting tsunami was described by Mader & Gittings, in 2006. A high wall of water is formed that

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2688-516: The bards and artists, the worship of the Hindu god Murugan and the monasteries of Buddhism and Jainism. Indica is an account of Mauryan India by the Greek writer Megasthenes . The original book is now lost, but its fragments have survived in later Greek and Latin works. The earliest of these works are those by Diodorus Siculus , Strabo ( Geographica ), Pliny , and Arrian ( Indica ). In

2772-576: The case. French historians associated with the Annales School introduced quantitative history, using raw data to track the lives of typical individuals, and were prominent in the establishment of cultural history. The Zuo zhuan , attributed to Zuo Qiuming in the 5th century BCE covers the period from 722 to 468 BCE in a narrative form. The Book of Documents is one of the Five Classics of Chinese classic texts and one of

2856-791: The clouds emerged blue and sometimes green. People also saw lavender suns and, for the first time, recorded noctilucent clouds . Although the violent phase of the 1883 eruption was over by the late afternoon of 27 August, after light returned by 29 August, reports continued for months that Krakatoa was still in eruption. Verbeek's committee's earliest duties were to determine if this was true and verify reports of other volcanoes erupting on Java and Sumatra. In general, these were found to be false. Small eruptions, mostly of mud, continued into October 1883. Verbeek discounted any claims of Krakatoa still erupting after mid-October due to steaming of hot material, landslides due to heavy monsoon rains that season, and "hallucinations due to electrical activity" seen from

2940-472: The corpses in Southern Sumatra appear to have been scorched to death, presumably by the pyroclastic flows. The Loudon and the W.H. Besse , at ~65 km north-northeast and ~80 km east-northeast of Krakatau respectively, were hit by strong winds and tephra. They were farther away than the scorched victims of the hot flows in Sumatra, so the ships and crew survived. The flows had moved across

3024-413: The destruction of all vegetation, leaving only tree stumps. He advised against any further landings. By 25 August, the Krakatoa eruptions intensified. At about 1:00 pm on 26 August, the eruption entered its climactic phase. By 2:00 pm, a black ash cloud could be seen 27 km (17 mi) high. At this point, the eruption was almost continuous, and explosions could be heard every ten minutes. By 5:00 pm,

3108-534: The door . . . I forced myself through the opening . . . I tripped and fell. I realized the ash was hot and I tried to protect my face with my hands. The hot bite of the pumice pricked like needles . . . Without thinking, I walked hopefully forward. Had I been in my right mind, I would have understood what a dangerous thing it was to . . . plunge into the hellish darkness . . . I ran up against . . . branches and did not even think of avoiding them. I entangled myself more and more . . . My hair got caught up . . . I noticed for

3192-534: The eardrums of sailors on RMS Norham Castle of the Castle Line which was hove to off Sumatra, and caused a spike of more than 8.5 kilopascals (2.5 inHg) in the pressure gauge attached to a gasometer in the Batavia (correspondent to modern day Jakarta) gasworks 160 km (100 miles) away, sending it off the scale. At Batavia, the air waves burst windows and cracked walls. The pressure wave

3276-568: The earliest civilizations of Early Dynastic Period of Egypt , Mesopotamia and the Sumerians , which emerged independently of each other from roughly 3500 BCE. Earliest recorded history, which varies greatly in quality and reliability, deals with Pharaohs and their reigns , as preserved by ancient Egyptians . Much of the earliest recorded history was re-discovered relatively recently due to archaeological dig sites findings. A number of different traditions have developed in different parts of

3360-584: The earliest narratives of China. The Spring and Autumn Annals , the official chronicle of the State of Lu covering the period from 722 to 481 BCE, is arranged on annalistic principles. It is traditionally attributed to Confucius (551–479 BCE). Zhan Guo Ce was a renowned ancient Chinese historical compilation of sporadic materials on the Warring States period compiled between the 3rd and 1st centuries BCE. Sima Qian (around 100 BCE)

3444-504: The eruption columns. This caused several cubic kilometres of material to enter the sea, displacing an equal volume of seawater. Smaller waves were recorded on tidal gauges as far away as the English Channel . These occurred too soon to be remnants of the initial tsunamis, which owing to a wavelength of less than 7 km, failed to cause significant damage at large distance, and may have been caused by concussive air waves from

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3528-516: The eruption is believed to have been a new vent or vents that formed on that day, between Perboewatan and Danan . The violence of the ongoing eruptions caused tides in the vicinity to be unusually high, and ships at anchor had to be moored with chains. Earthquakes were felt at Anyer , Banten , and ships began to report large pumice masses to the west in the Indian Ocean . A third vent, and later many more, appeared. The eruptions continued throughout July, and their violence continued to increase until

3612-428: The eruption. These air waves circled the globe several times and were still detectable on barographs five days later. About 10% of the eruption fatalities were from hot pyroclastic flows and falling tephra. The pyroclastic flows and surges produced by the third explosion moved faster than 100 km/h (62 mph) and travelled over the sea up to 80 km (50 mi) from the source, affecting an area constrained to

3696-421: The explosions of 27 August. In early August, a Dutch topographical engineer, Captain H. J. G. Ferzenaar, investigated the Krakatoa islands. He noted three major ash columns (the newer from Danan), which obscured the western part of the island, and steam plumes from at least eleven other vents, mostly between Danan and Rakata . When he landed, he noted an ash layer about 0.5 m (1 ft 8 in) thick and

3780-412: The explosions were audible all over Java. Waves a few feet in height began battering the coasts of Java and Sumatra at 5:30 pm, and continued throughout the night, which may have been produced by steam explosions. Ships within 20 km (12 mi) of the volcano reported heavy ash fall, with pieces of hot pumice up to 10 cm (4 in) in diameter landing on their decks. Between 7:00 pm and 8:00 pm,

3864-468: The extremely strong 2014–2016 El Niño , climate change , or some other factor might be involved. They are trying to determine whether this is more of a once-in-a-generation event or a sign of the changing climate. 1883 eruption of Krakatoa The 1883 eruption of Krakatoa ( Indonesian : Letusan Krakatau 1883 ) in the Sunda Strait occurred from 20 May until 21 October 1883, peaking in

3948-581: The first time that [my] skin was hanging off everywhere, thick and moist from the ash stuck to it. Thinking it must be dirty, I wanted to pull bits of skin off, but that was still more painful . . . I did not know I had been burnt." — Mrs. Beyerinck (of Ketimbang) An estimated 20 cubic kilometres of tephra was deposited. Ash was propelled to an estimated height of 80 km (50 mi). It is estimated that as much as 18–21 km (4.3–5.0 cu mi) of ignimbrite were deposited over 1,100,000 km (420,000 sq mi). Around noon on 27 August 1883,

4032-515: The full impact of natural disasters or the names of individuals. Recorded history for particular types of information is therefore limited based on the types of records kept. Because of this, recorded history in different contexts may refer to different periods of time depending on the topic. The interpretation of recorded history often relies on historical method , or the set of techniques and guidelines by which historians use primary sources and other evidence to research and then to write accounts of

4116-409: The globe more than three times. At least 36,417 deaths are attributed to the eruption and the tsunamis it created. Significant additional effects were felt worldwide in the days and weeks after the volcano's eruption. Additional seismic activity was reported until February 1884, but any reports after October 1883 were dismissed by Rogier Verbeek 's subsequent investigation into the eruption. In

4200-462: The imminent danger; the ship had just enough time to meet with the wave from the front. The ship met the wave head on and the Loudon was lifted up with a dizzying rapidity and made a formidable leap... The ship rode at a high angle over the crest of the wave and down the other side. The wave continued on its journey toward land, and the benumbed crew watched as the sea in a single sweeping motion consumed

4284-460: The initial violence. Around 16 June, there were loud explosions and a thick black cloud covered the islands for five days. The eruptions started gaining strength again on 19 June. On 24 June, a prevailing east wind cleared the cloud, and two ash columns could be seen issuing from Krakatoa. It was also noticed that the summit cone of Perboewatan was gone, which an extensive report of a few years later attributes it to having been blown away. The seat of

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4368-451: The island on 26 May reported that the islands were covered with a fine white dust, with explosions coming from Perboewatan every 5 to 10 minutes. Although by this time the eruptions were calming down, some of the explosions were still very energetic, hurling pumice opposite the direction of the wind. A large crater about 3,000 feet (900 metres) in diameter formed, with a cavity from which issued plumes of steam. The eruptions soon quietened after

4452-509: The late morning of 27 August when over 70% of the island of Krakatoa and its surrounding archipelago were destroyed as it collapsed into a caldera . The eruption was one of the deadliest and most destructive volcanic events in recorded history . The explosion was heard 3,110 kilometres (1,930 mi) away in Perth , Western Australia, and Rodrigues near Mauritius , 4,800 kilometres (3,000 mi) away. The acoustic pressure wave circled

4536-444: The low-lying Thousand Islands were submerged under 2 meters (6.6 feet) of seawater, forcing people to climb trees. The tsunamis produced by the third explosion were the largest, although the first two explosions did produce smaller tsunamis. The town of Merak was destroyed by a tsunami that was 46 metres high. The waves reached heights of up to 24 metres (79 feet) along the south coast of Sumatra and up to 42 metres (138 feet) along

4620-432: The object of study." Historians use other types of sources to understand history as well. Secondary sources are written accounts of history based upon the evidence from primary sources. These are sources which, usually, are accounts, works, or research that analyse, assimilate, evaluate, interpret, and/or synthesize primary sources. Tertiary sources are compilations based upon primary and secondary sources and often tell

4704-443: The past. The question of what constitutes history, and whether there is an effective method for interpreting recorded history, is raised in the philosophy of history as a question of epistemology . The study of different historical methods is known as historiography , which focuses on examining how different interpreters of recorded history create different interpretations of historical evidence. Prehistory traditionally refers to

4788-481: The period during which a culture or civilization has not yet developed writing, but other cultures have noted its existence in their own writings. More complete writing systems were preceded by proto-writing . Early examples are the Jiahu symbols ( c.  6600 BCE ), Vinča signs ( c.  5300 BCE ), early Indus script ( c.  3500 BCE ) and Nsibidi script ( c.  before 500 CE ). There

4872-443: The phenomenon the "equatorial smoke stream". This was the first identification of what is known today as the jet stream . For several years following the eruption, it was reported that the moon appeared to be blue and sometimes green. This was because some ash clouds were filled with particles about 1  μm wide – the right size to strongly scatter red light while allowing other colours to pass. White moonbeams shining through

4956-530: The preface to his book, the Muqaddimah (1377), the Arab historian and early sociologist , Ibn Khaldun , warned of seven mistakes that he thought that historians regularly committed. In this criticism, he approached the past as strange and in need of interpretation. Ibn Khaldun often criticised "idle superstition and uncritical acceptance of historical data." As a result, he introduced a scientific method to

5040-620: The prestigious Ban family of the Eastern Han dynasty era. In Sri Lanka , the oldest historical text is the Mahavamsa ( c. 5th century CE). Buddhist monks of the Anuradhapura Maha Viharaya maintained chronicles of Sri Lankan history starting from the 3rd century BCE. These annals were combined and compiled into a single document in the 5th century by the Mahanama of Anuradhapura while Dhatusena of Anuradhapura

5124-452: The remainder of the island to the north of Rakata, causing the final explosion. The sounds of the eruption of the Krakatoa volcano were estimated to be 310 dB SPL, and there are reports that it was heard some 1,300 miles away in the Bay of Bengal. Some islands in the western Indian Ocean, approximately 3,000 miles away, still heard it at a dB level near the same level as a gun blast. Due to

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5208-618: The result of divine intervention. History developed as a popular form of literature in later Greek and Roman societies in the works of Polybius , Tacitus and others. Saint Augustine was influential in Christian and Western thought at the beginning of the medieval period. Through the Medieval and Renaissance periods, history was often studied through a sacred or religious perspective. Around 1800, German philosopher and historian Georg Wilhelm Friedrich Hegel brought philosophy and

5292-423: The span of time before recorded history, ending with the invention of writing systems . Prehistory refers to the past in an area where no written records exist, or where the writing of a culture is not understood. Protohistory refers to the transition period between prehistory and history, after the advent of literacy in a society but before the writings of the first historians . Protohistory may also refer to

5376-411: The speed of sound, it is likely the people on these far away islands did not hear Krakatoa for nearly four hours after its eruption. The pressure wave generated by the colossal third explosion radiated out from Krakatoa at 1,086 km/h (675 mph). The eruption is estimated to have reached 180 dB, loud enough to be heard 5,000 kilometres (3,100 mi) away. It was so powerful that it ruptured

5460-536: The state of the affected areas, where the village of Tjaringin once was. "Thousands of corpses of human beings and also carcasses of animals still await burial, and make their presence apparent by the indescribable stench. They lie in knots and entangled masses impossible to unravel, and often jammed along with coconut stems among all that had served these thousands as dwellings, furniture, farming implements, and adornments for houses and compounds." -- From Zeilinga de Boer and Sanders, 2002 The official reported death toll

5544-464: The study of history, and he often referred to it as his "new science". His historical method also laid the groundwork for the observation of the role of state , communication , propaganda and systematic bias in history, and he is thus considered to be the "father of historiography" or the "father of the philosophy of history". While recorded history begins with the invention of writing, over time new ways of recording history have come along with

5628-590: The sun than usual and cooled the entire planet until the sulphur fell to the ground as acid precipitation . The 1883 Krakatoa eruption darkened the sky worldwide for years afterwards and produced spectacular sunsets worldwide for many months. British artist William Ascroft made thousands of colour sketches of the red sunsets halfway around the world from Krakatoa in the years after the eruption. The ash caused "such vivid red sunsets that fire engines were called out in New York , Poughkeepsie , and New Haven to quench

5712-520: The techniques and guidelines by which historians use primary sources and other evidence to research and then to write history . Primary sources are first-hand evidence of history (usually written, but sometimes captured in other mediums) made at the time of an event by a present person. Historians think of those sources as the closest to the origin of the information or idea under study. These types of sources can provide researchers with, as Dalton and Charnigo put it, "direct, unmediated information about

5796-527: The time, were thought to contradict the 1883 findings. However, the winds that would become known as the QBO were discovered to oscillate between westerly and easterly in the 1950s by researchers at the UK Meteorological Office . The cause of these QBO winds remained unclear for some time. Radiosonde soundings showed that its phase was not related to the annual cycle , as is the case for many other stratospheric circulation patterns. In

5880-460: The town. There, where an instant before had lain the town of Telok Betong, nothing remained but the open sea." A farm worker who was near Merak on Monday morning reports: " . . .all of a sudden there came a great noise. We . . .saw a great black thing, a long way off, coming towards us. It was very high and very strong, and we soon saw that it was water. Trees and houses were washed away . . .The people began to . . . run for their lives. Not far off

5964-504: The volcano at 2,575 kilometres per hour (715 metres per second). The energy released from the explosion has been estimated to be equal to about 200 megatonnes of TNT (840 petajoules ), roughly four times as powerful as the Tsar Bomba , the most powerful thermonuclear weapon ever detonated. This makes it one of the most powerful explosions in recorded history. At 10:41   am, a landslide tore off half of Rakata volcano, along with

6048-475: The volcano has been calculated to have been 180 dB . Each explosion was accompanied by tsunamis estimated to have been over 30 metres (98 feet) high in places. A large area of the Sunda Strait and places on the Sumatran coast were affected by pyroclastic flows from the volcano. Verbeek and others believe that the final major Krakatoa eruption was a lateral blast , or pyroclastic surge . Material shot out of

6132-459: The water on a cushion of superheated steam. There are also indications of submarine pyroclastic flows reaching 15 km (9.3 mi) from the volcano. An eyewitness enveloped by the outermost edges of the pyroclastic flow described her experience: "Suddenly, it became pitch dark. The last thing I saw was the ash being pushed up through the cracks in the floorboards, like a fountain. I turned to my husband and heard him say in dispair ' Where

6216-423: The west coast of Java . The tsunamis washed the land clean of vegetation and destroyed human settlements. The Loudon , which at the time was anchored near the village of Telok Betong, survived the waves. Passengers produced this eyewitness account: "Suddenly we saw a gigantic wave of prodigious height advancing toward the seashore with considerable speed. Immediately, the crew . . .managed to set sail in face of

6300-427: The world as to how to interpret these ancient accounts. Dionysius of Halicarnassus knew of seven predecessors of Herodotus , including Hellanicus of Lesbos , Xanthus of Lydia and Hecataeus of Miletus . He described their works as simple, unadorned accounts of their own and other cities and people, Greek or foreign, including popular legends. Herodotus (484 BCE – c. 425 BCE) has generally been acclaimed as

6384-708: The years before the 1883 eruption, seismic activity around the Krakatoa volcano was intense, with earthquakes felt as far away as North Australia, one of which, in 1880, damaged a lighthouse. Strombolian activity began on 20 May 1883, and steam venting began to occur regularly from Perboewatan , the northernmost of the island's three cones. Eruptions of ash reached an estimated altitude of 6 km (20,000 ft), and explosions could be heard in Batavia ( Jakarta ) 160 km (100 mi) away, rattling windows and doors. Dust fell 300 miles away. An excursion party sent to

6468-468: Was 36,417. There were no survivors from the 3,000 people on the island of Sebesi . In the aftermath of the eruption, it was found that Krakatoa had almost entirely disappeared, except for the southern third. Much of the Rakata cone had been sheared away, leaving behind a 250-metre (820 ft) cliff. Of the northern two-thirds of the island, only a rocky islet named Bootsmansrots (' Bosun 's Rock'),

6552-481: Was killed in Sri Lanka. Ships as far away as South Africa rocked as tsunamis hit them, and the victims' bodies were found floating in the ocean for months after the event. The tsunamis which accompanied the eruption were believed to have been caused by gigantic pyroclastic flows entering the sea; each of the four great explosions was accompanied by large pyroclastic flows resulting from the gravitational collapse of

6636-606: Was noted beginning in February 2016, when the transition to easterly winds was disrupted by a new band of westerly winds that formed unexpectedly. The lack of a reliable QBO cycle deprives forecasters of a valuable tool. Since the QBO has a strong influence on the North Atlantic Oscillation and thereby north European weather, scientists speculated that the coming winter could be warmer and stormier in that region. NASA scientists have been researching to test if

6720-426: Was recorded on barographs worldwide. Several barographs recorded the wave seven times over five days: four times with the wave travelling away from the volcano to its antipodal point and three times travelling back to the volcano. Hence, the wave rounded the globe three and a half times. Massive tsunamis struck the coastlines of the Sunda Strait, entirely submerging some islands. Some 80 km (50 mi) away,

6804-710: Was ruling the Anuradhapura Kingdom . It was written based on prior ancient compilations known as the Atthakatha , which were commentaries written in Sinhala. An earlier document known as the Dipavamsa (4th century CE) "Island Chronicles" is much simpler and contains less information than the Mahavamsa and was probably compiled using the Atthakatha on the Mahavamsa as well. A companion volume,

6888-470: Was so powerful that it was heard 3,110 km (1,930 mi) away in Perth , Western Australia, and the Indian Ocean island of Rodrigues near Mauritius , 4,800 km (3,000 mi) away, where the blast was thought to have been cannon fire from a nearby ship. The third explosion has been reported as the loudest sound in history. The loudness of the blast heard 160 km (100 mi) from

6972-520: Was some steep sloping ground. We all ran towards it and tried to climb up out of the way of the water. The wave was too quick for most of them, and many were drowned almost at my side. . . . There was a general rush to climb up in one particular place. This caused a great block, and many of them got wedged together and could not move. Then they struggled and fought, screaming and crying out all the time. Those below tried to make those above them move on again by biting their heels. A great struggle took place for

7056-694: Was the first in China to lay the groundwork for professional historical writing. His written work was the Records of the Grand Historian , a monumental lifelong achievement in literature. Its scope extends as far back as the 16th century BCE, and it includes many treatises on specific subjects and individual biographies of prominent people, and also explores the lives and deeds of commoners, both contemporary and those of previous eras. His work influenced every subsequent author of history in China, including

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